This paper presents and analyzes a monotone domain decomposition algorithm for solving nonlinear singularly perturbed reaction-diffusion problems of parabolic type. To solve the nonlinear weighted average finite diffe...This paper presents and analyzes a monotone domain decomposition algorithm for solving nonlinear singularly perturbed reaction-diffusion problems of parabolic type. To solve the nonlinear weighted average finite difference scheme for the partial differential equation, we construct a monotone domain decomposition algorithm based on a Schwarz alternating method and a box-domain decomposition. This algorithm needs only to solve linear discrete systems at each iterative step and converges monotonically to the exact solution of the nonlinear discrete problem. domain decomposition algorithm is estimated The rate of convergence of the monotone Numerical experiments are presented.展开更多
By using the Feynman-Kac formula and combining with Itˆo-Taylor expansion and finite difference approximation,we first develop an explicit third order onestep method for solving decoupled forward backward stochastic d...By using the Feynman-Kac formula and combining with Itˆo-Taylor expansion and finite difference approximation,we first develop an explicit third order onestep method for solving decoupled forward backward stochastic differential equations.Then based on the third order one,an explicit fourth order method is further proposed.Several numerical tests are also presented to illustrate the stability and high order accuracy of the proposed methods.展开更多
Based on the input-output data from 2002 to 2017,this paper combined the three-stage DEA model with the non-competitive I-O model and measured the embodied carbon efficiency of export trade in China’s 26 product sect...Based on the input-output data from 2002 to 2017,this paper combined the three-stage DEA model with the non-competitive I-O model and measured the embodied carbon efficiency of export trade in China’s 26 product sectors,and further investigated its influencing factors and convergence issues.The results of the study showed that:①The embodied carbon efficiency of export trade in China’s overall product sector demonstrated a positive development trend from 2002 to 2017,and this positive trend was more obvious after the implementation of conservation culture construction in 2012.But the differences of embodied carbon emission efficiency level among the product sectors were still significant.②Measured by the K-means clustering analysis method,this study found that agriculture,other service industries,wholesale and retail industries,catering industry,construction industry and manufacturing industry with strong innovation ability were mostly concentrated at high and medium efficiency levels,while industrial sectors with resource dependence and high energy consumption,such as metal smelting and rolling processing industries,non metallic mineral products industry,and coal mining industry,were at a low efficiency level.③All product sectors hadσconvergence,absoluteβconvergence and conditionalβconvergence during 2002-2010 and 2010-2017,and the level of each product sector in 2010-2017 was higher than that in 2002-2010 according to the perspective of convergence speed and degree of convergence.④Technological progress had not fully played a role in suppressing energy consumption and improving the efficiency of embodied carbon efficiency,and it would also widen the gap between the embodied carbon emission efficiency levels of various product sectors.The expansion of trade scale could effectively improve carbon emission efficiency and narrow the gap between sectors.Environmental regulation could effectively promote the improvement of embodied carbon emission efficiency but would widen the level gap between sectors展开更多
在国内外研究的基础上,对印太暖池区的沃克环流和厄尔尼诺-南方涛动(ENSO)、热带辐合带(ITCZ)等低纬过程的空间分布和随时间的变化规律及其研究方法进行初步归纳,并指出研究中存在的问题。本文论述了厄尔尼诺-南方涛动变率在全新世早期...在国内外研究的基础上,对印太暖池区的沃克环流和厄尔尼诺-南方涛动(ENSO)、热带辐合带(ITCZ)等低纬过程的空间分布和随时间的变化规律及其研究方法进行初步归纳,并指出研究中存在的问题。本文论述了厄尔尼诺-南方涛动变率在全新世早期及中世纪气候异常期(1 000~700 a BP)的晚期逐渐增强,介绍了热带辐合带在BA暖期(B?llingAller?d Warm Period)和前北方期(pre-Boreal,10.3~9.5 ka BP)的北移,以及在新仙女木事件(Younger Dryas Event,12.5~11.5 ka BP)和北大西洋冷期(距今7.5~5 ka BP)期间的南移。对低纬过程长时间尺度轨道周期的探讨表明,末次冰盛期赤道东太平洋出现了较偏南的热带辐合带锋面系统,甚至在1.65 Ma冰期,热带辐合带也有快速南移的证据。海洋沉积的粒度、黏土矿物、陆源粉尘、元素和同位素、有孔虫分析等研究方法在推测厄尔尼诺-南方涛动和热带辐合带位移中有很好的应用,建议以陆源生态系统对气候的响应为切入点、以孢粉为手段来探讨陆源植被、气候、火灾和海-陆大气环流等低纬过程的变化特征,进而反演沃克环流(或厄尔尼诺-南方涛动)演化和热带辐合带位移的影响。展开更多
文摘This paper presents and analyzes a monotone domain decomposition algorithm for solving nonlinear singularly perturbed reaction-diffusion problems of parabolic type. To solve the nonlinear weighted average finite difference scheme for the partial differential equation, we construct a monotone domain decomposition algorithm based on a Schwarz alternating method and a box-domain decomposition. This algorithm needs only to solve linear discrete systems at each iterative step and converges monotonically to the exact solution of the nonlinear discrete problem. domain decomposition algorithm is estimated The rate of convergence of the monotone Numerical experiments are presented.
基金supported by the NSF of China(No.12001539)the NSF of Hunan Province(No.2020JJ5647)China Postdoctoral Science Foundation(No.2019TQ0073).
文摘By using the Feynman-Kac formula and combining with Itˆo-Taylor expansion and finite difference approximation,we first develop an explicit third order onestep method for solving decoupled forward backward stochastic differential equations.Then based on the third order one,an explicit fourth order method is further proposed.Several numerical tests are also presented to illustrate the stability and high order accuracy of the proposed methods.
基金Project of Basic Work of Science and Technology of Guizhou Provincial Science and Technology Department in 2020,“Quantification of Ecological Compensation in Southwest China Based on Carbon Balance”[Grant number.Guizhou Science Cooperation Basic Project[2020]1Y287]Research Fund Project of Guizhou University of Finance and Economics in 2020,“Research on the Influencing Factors of China's Low-carbon Trade Competitiveness”[Grant number.2020XJC01].
文摘Based on the input-output data from 2002 to 2017,this paper combined the three-stage DEA model with the non-competitive I-O model and measured the embodied carbon efficiency of export trade in China’s 26 product sectors,and further investigated its influencing factors and convergence issues.The results of the study showed that:①The embodied carbon efficiency of export trade in China’s overall product sector demonstrated a positive development trend from 2002 to 2017,and this positive trend was more obvious after the implementation of conservation culture construction in 2012.But the differences of embodied carbon emission efficiency level among the product sectors were still significant.②Measured by the K-means clustering analysis method,this study found that agriculture,other service industries,wholesale and retail industries,catering industry,construction industry and manufacturing industry with strong innovation ability were mostly concentrated at high and medium efficiency levels,while industrial sectors with resource dependence and high energy consumption,such as metal smelting and rolling processing industries,non metallic mineral products industry,and coal mining industry,were at a low efficiency level.③All product sectors hadσconvergence,absoluteβconvergence and conditionalβconvergence during 2002-2010 and 2010-2017,and the level of each product sector in 2010-2017 was higher than that in 2002-2010 according to the perspective of convergence speed and degree of convergence.④Technological progress had not fully played a role in suppressing energy consumption and improving the efficiency of embodied carbon efficiency,and it would also widen the gap between the embodied carbon emission efficiency levels of various product sectors.The expansion of trade scale could effectively improve carbon emission efficiency and narrow the gap between sectors.Environmental regulation could effectively promote the improvement of embodied carbon emission efficiency but would widen the level gap between sectors
文摘在国内外研究的基础上,对印太暖池区的沃克环流和厄尔尼诺-南方涛动(ENSO)、热带辐合带(ITCZ)等低纬过程的空间分布和随时间的变化规律及其研究方法进行初步归纳,并指出研究中存在的问题。本文论述了厄尔尼诺-南方涛动变率在全新世早期及中世纪气候异常期(1 000~700 a BP)的晚期逐渐增强,介绍了热带辐合带在BA暖期(B?llingAller?d Warm Period)和前北方期(pre-Boreal,10.3~9.5 ka BP)的北移,以及在新仙女木事件(Younger Dryas Event,12.5~11.5 ka BP)和北大西洋冷期(距今7.5~5 ka BP)期间的南移。对低纬过程长时间尺度轨道周期的探讨表明,末次冰盛期赤道东太平洋出现了较偏南的热带辐合带锋面系统,甚至在1.65 Ma冰期,热带辐合带也有快速南移的证据。海洋沉积的粒度、黏土矿物、陆源粉尘、元素和同位素、有孔虫分析等研究方法在推测厄尔尼诺-南方涛动和热带辐合带位移中有很好的应用,建议以陆源生态系统对气候的响应为切入点、以孢粉为手段来探讨陆源植被、气候、火灾和海-陆大气环流等低纬过程的变化特征,进而反演沃克环流(或厄尔尼诺-南方涛动)演化和热带辐合带位移的影响。
